SSZ-13 as a catalyst for conversion of chloromethane to olefins

Abstract

Disclosed are methods and systems for converting chloromethane to olefins. A method includes contacting an aluminosilicate catalyst having a chabazite zeolite structure with a feed that includes an alkyl halide and is substantially free of oxygenates under reaction conditions sufficient to produce an olefin hydrocarbon product comprising C 2 -C 4 olefins.

The invention claimed is: 
     
       1. A method for converting an alkyl halide to an olefin, the method comprising contacting an aluminosilicate catalyst having a chabazite zeolite structure with a feed comprising an alkyl halide under reaction conditions sufficient to produce an olefin hydrocarbon product comprising C 2 -C 4  olefins, wherein the feed is substantially free of oxygenates, wherein the aluminosilicate catalyst is SSZ-13. 
     
     
       2. The method of  claim 1 , wherein the feed comprises at least 50 wt. %, at least 75 wt. %, at least 80 wt. %, or at least 90 wt. % alkyl halide. 
     
     
       3. The method of  claim 1 , wherein the aluminosilicate catalyst has a silica (SiO 2 ) to alumina (Al 2 O 3 ) mole ratio (SAR) of less than 100:1. 
     
     
       4. The method of  claim 3 , wherein the SAR is 30:1 to 50:1. 
     
     
       5. The method of  claim 3 , wherein the SAR is 65:1 to 85:1. 
     
     
       6. The method of  claim 1 , wherein the feed stream includes less than 5 wt. % alcohol. 
     
     
       7. The method of  claim 6 , wherein the alcohol is methanol or ethanol. 
     
     
       8. The method of  claim 1 , wherein the feed stream includes less than 5 wt. % oxygenates. 
     
     
       9. The method of  claim 1 , wherein the alkyl halide is a methyl halide. 
     
     
       10. The method of  claim 9 , wherein the methyl halide is methyl chloride, methyl bromide, methyl fluoride, or methyl iodide, or any combination thereof. 
     
     
       11. The method of  claim 10 , wherein the methyl halide is methyl chloride. 
     
     
       12. The method of  claim 1 , wherein the reaction occurs in a fluid catalytic cracking (FCC) reactor or fluidized circulating bed reactor. 
     
     
       13. The method of  claim 1 , wherein the reaction conditions include a temperature from 300° C. to 500° C., a pressure of 0.5 MPa or less, and a weighted hourly space velocity (WHSV) of 0.5 to 10 h −1 . 
     
     
       14. The method of  claim 13 , wherein the maximum combined selectivity of ethylene and propylene is at least 65% or 65% to 75%, wherein the maximum combined space time yield of ethylene and propylene is at least 1/hr or 1/hr to 3/hr, and/or wherein the maximum conversion of alkyl halide is at least 70% or 80% to 100%. 
     
     
       15. The method of  claim 14 , wherein the maximum selectivity of ethylene is 50% to 70% and the maximum selectivity of propylene is 60% to 80%. 
     
     
       16. The method of  claim 1 , further comprising collecting or storing the produced olefin hydrocarbon product. 
     
     
       17. The method of  claim 1 , further comprising using the produced olefin hydrocarbon product to produce a petrochemical or a polymer. 
     
     
       18. The method of  claim 1 , further comprising regenerating used/deactivated catalyst in a continuous process such as a fluid catalytic cracking (FCC)-type process or reactor or a circulating catalyst bed process or reactor. 
     
     
       19. A system for producing olefins, the system comprising:
 an inlet for a feed comprising an alkyl halide, wherein the feed is substantially free of oxygenates; 
 a reaction zone that is configured to be in fluid communication with the inlet, wherein the reaction zone comprises the feed and an aluminosilicate catalyst having a chabazite zeolite structure, wherein the aluminosilicate catalyst is SSZ-13; and 
 an outlet configured to be in fluid communication with the reaction zone to remove an olefin hydrocarbon product from the reaction zone. 
 
     
     
       20. A method for converting an alkyl halide to an olefin, the method comprising contacting an aluminosilicate catalyst having a chabazite zeolite structure with a feed comprising an alkyl halide under reaction conditions sufficient to produce an olefin hydrocarbon product comprising C 2 -C 4  olefins, wherein the feed is substantially free of oxygenates, wherein the aluminosilicate catalyst has a silica (SiO 2 ) to alumina (Al 2 O 3 ) mole ratio (SAR) of less than 100:1.